酶法制备大豆多肽的分子量分布和抑瘤实验观察

目的观察复合酶法制备的大豆多肽,其分子量分布和体内外的抑瘤作用。方法Flavourzyme、Alealase和中性蛋白酶,pH7.0,50～55℃酶解,经分离、离心、喷雾干燥等工艺制成多肽干粉;样品以0.1mol/L Tris-HCl缓冲液为洗脱液,流速0.5ml/min过SephadexG25凝胶柱,分别收集,紫外分光仪280nm波长测定各管的吸收值,并用高效液相排阻色谱法对比同样品测定,计算确定分子量分布;小鼠脑胶质瘤G422体内抑瘤实验,给药剂量1.25、2.50、5.00g/kgbw,人喉鳞状细胞癌Hep-2细胞体外抑瘤实验,分5个样品浓度mg/ml。结果复合酶法生产制备大豆多肽3批,各批干基肽含量分别54.6%、51.9%、51.8%;Mr≤1000U占总量50%以上。小鼠脑胶质瘤G422体内实验,剂量5g/kgbw组与对照相比多肽有41.2%的抑瘤率(P<0.05),人喉癌Hep-2体外实验结果多肽无直接细胞毒作用。结论紫外分光法与高效液相色谱法测定大豆多肽分子量分布结果基本相同。小鼠G422实验在高剂量组观察到有抑瘤作用。

DISTRIBUTION OF MOLECULAR WEIGHT OF PEPTIDE PREPARED BY COMPLEX ENZYME AND THE TUMOR INHIBITION TEST

Objective To observe the molecular weight distribution of soybean peptides prepared by complex enzyme hydrolysation and tumor inhibitory effect in vivo or in vitro. Method The soybean protein was enzymolyzed to soybean peptides by Flavourzyme, Alealase and neutral protease, at(50-55)℃, followed by separation, absorption,affination, ultra centrifuge and spray drying. The soybean peptides were passed Sephadex G25 column at 0.5ml/min with 0.1mol/L Tris-HCl buffer. The fragment of fluid collected was determined by UV at 280nm and HPLC. Then the molecular weight distribution was calculated. The inhibitory effect on ansplant glioma (G422) at dose 1.25, 2.5 and 5g/kg bw (ig daily for 11 d) was tested in mice and in Hep-2 in vitro. Results The peptides contents in three batches were 54.6%, 51.9%, 51.8% respeclively. The molecular weight <1000 U reached about 50%. Compared with control group, the inhibitory rate was 41.2% (P<0.05). Conclusion The molecular weight distrubition in soybean peptides< 1000 U reached about 50%. The tumor inhibitory effect was observed at dose of 5g/kg bw.